There's no short-term incentive to shareholders if the company has raised, through private placement, enough money to keep them going for a while.
The valuation isn't important to them; they won't be raising capital by issuing stock. You could argue that a higher valuation would make them more willing to be bought out, but there's no evidence that's the case.
Unless of course, there's an ulterior motive. So far they haven't diluted, so I'll give them credit for that.